Former President Martinelli faces charges of spying on journalists and political opponents in his homeland.

Panama's former President Ricardo Martinelli has been extradited to his homeland from the United States, where he has been held on charges of political espionage and corruption, one of his lawyers said.

Martinelli, who was president from 2009-2014, was transferred from the federal prison in Miami to the Opa Locka Executive Airport, where he was placed on a charter flight to Panama City at around 10:20 GMT.

A handcuffed Martinelli, escorted by US officers, greeted reporters gathered at the airport.

"I'm ready to watch the World Cup!" he said, giving a thumbs-up. Panama qualified for the tournament, which begins on Thursday.

Martinelli was taken into custody near his home in the US state of Florida in June 2017 after Panama requested his extradition on charges that he used public money to spy on more than 150 political rivals during his 2009-2014 term.

He claims that he is the victim of a "vendetta" by Panamanian President Juan Carlos Varela, his former vice president. He has denied wrongdoing and contends that the case amounts to political persecution by his successor.

Varela served as Martinelli's vice president but they have sparred bitterly since the transfer of power.

The 66-year-old is under investigation in Panama in about 20 other cases of corruption, but those are not referred to in the extradition request.

Under a 1905 extradition treaty, he can only be tried in Panama for the crimes alleged in the request.

Martinelli is barred by term limits from running for president before 2024, but he hopes to run for a mayorship or a congressional seat, his spokesman Luis Eduardo Camacho has said.

A supermarket tycoon, Martinelli presided over an infrastructure boom and Latin America's fastest economic growth in recent years, but his administration was tainted by allegations of corruption.